One well-known type of extracorporeal blood processing involves an aphaeresis system and procedure in which blood is removed from a donor or a patient (hereafter cumulatively referred to as a donor), directed to a blood component separation device (e.g., centrifuge), and separated into various blood component types (e.g., red blood cells, white blood cells, platelets, plasma) for collection or therapeutic purposes. One or more or all of these blood component types may either be collected and treated for therapeutic purposes before storage or returned to a patient, while the remainder may simply be returned to the donor or patient.
A number of factors may affect the commercial viability of an aphaeresis system. One factor relates to the time and expertise required of an individual to prepare and operate the aphaeresis system. For instance, reducing the time required by the operator to complete an entire collection procedure, as well as reducing the complexity of these actions, can increase productivity or lower the potential for operator error. Moreover, reducing the dependency of the system on the operator may further lead to reductions in the credentials desired/required for the operators of these systems.
Performance-related factors also affect the commercial viability of an aphaeresis system. Performance may be judged in terms of the collection efficiency of the aphaeresis system, which may impact or improve product quality and/or may in turn reduce the amount of processing time and thus decrease operator burden and increase donor convenience. The collection efficiency of a system may of course be gauged in a variety of ways, such as by the amount of a particular blood component type which is collected in relation to the quantity of this blood component type which passes through the aphaeresis system. Performance may also be evaluated based upon the effect which the aphaeresis procedure has on the various blood component types. For instance, it is desirable to minimize the adverse effects on the blood component types as a result of the aphaeresis procedure.
In particular, concerns have arisen regarding plasma-induced transfusion reactions in certain patients. Efforts have been made to produce platelet components (or “products”) with lower plasma concentration and with PAS used as a storage solution. Such platelet products may have high platelet concentrations, for example between 3000 and 5000 platelets per milliliter. There remains a need, however, to produce a platelet product with as little residual plasma as possible, thereby reducing or eliminating plasma-induced transfusion reactions.
An apparatus and method for red blood cell filtration in conjunction with aphaeresis separation is also disclosed in the commonly-owned U.S. patent application Ser. No. 09/672,519, filed Sep. 27, 2000, herein incorporated by reference. Further background on aphaeresis red blood cell separation and collection can be found in the PCT publication WO99/11305, which is also incorporated herein by this reference. Commonly-owned U.S. Pat. No. 7,052,606 is directed to red blood cell filtration, but also discusses the need to add storage solution to a collected blood component and certain means whereby storage solution may be added to the collected component. Commonly-owned U.S. patent application Ser. No. 12/234,960 (Publication US2009/0166298) describes the controlled addition of PAS to a blood component.